Chennai on a Rainwater Harvesting spree: Are we on the right track?

[dropcap]E[/dropcap]MPTY pots, depleting groundwater levels and cracked soil. This characterises the situation of Chennai that reached day zero this year and had to look out for alternative options such as transporting water through trains to meet the city’s water demand.

Having learnt a lesson from the current water scarcity, the Greater Chennai Corporation is all set to map two lakh buildings in the city to implement Rainwater Harvesting (RWH) over the next four months. While the civic body’s move is a welcome measure, it raises pertinent questions: did Tamil Nadu, a pioneer in legalising RWH fail to implement it? Is the City Corporation too late in streamlining RWH in Chennai? Why is the civic body not harvesting open spaces?

 

The law

 

Chennai Corporation’s Rainwater Harvesting mantra is not a new term in Tamil Nadu legal books, as the then Chief Minister J Jayalalithaa pushed for it in 2001. An amendment was made to Section 215(a) of the Tamil Nadu District Municipalities Act, 1920 and Building Rules 1973, to make RWH mandatory for government buildings and new buildings respectively.

“In every building owned or occupied by the Government or a statutory body or a company or an institution-owned or controlled by the Government, rainwater harvesting structure shall be provided by the Government or by such statutory body or company or other institution, as the case may be, in such manner and within such time as may be prescribed,” states Section 215(a).

In terms of numbers, the Tamil Nadu government has done fairly well in introducing rainwater harvesting structures in government offices. “Of the 24,116 Town Panchayat buildings in the state, 23,190 of them have RWH structures,” according to the data availed from Directorate of Town Panchayats office. In Chennai, 97 per cent of government buildings are compliant with the law, according to a highly placed official with Public Works Department (PWD).

 

The breach

 

But the ground reality is different. Most of the RWH structures are either old or in dire need of a revamp – the contrasting reality that provides an answer to the severe water shortage and flooding in Chennai. A quick observation at the offices of Public Works Department (PWD), Tamil Nadu Water Supply and Drainage Board Office (TWAD) and Tamil Nadu Small Industries Development Corporation Limited (SIDCO) reveal that the offices are not fully compliant with RWH. At the SIDCO office at Guindy, there is no facility to recharge the run-off water, which stagnates on the road.

“There is a shortage of funds due to which RWH structures have not been maintained properly,” a highly placed official from the PWD office said. The PWD is the nodal agency to maintain government buildings in the state, which includes setting up and maintaining RWH structures.

Most of the structures set up at least fifteen years ago follow outdated procedures that experts say, are ineffective. The trench area is filled with pebbles to clear the dirt in the rainwater, but it has a disadvantage. “It is not necessary to include pebbles in the trench area as they get clogged easily. Just letting the soil be in the trench area is effective as the layers of soil act best as a filter,” says Sekhar Raghavan of The Rain Centre.

The PWD official also admitted that the trench areas in most of the government offices had pebbles, which had not been unclogged in a long time.

 

What about harvesting in open places?

 

The very fact that the arterial roads that are a hub for government buildings such as Walajah Road (that has directorate of the Tourism office and Commissionerate of Agriculture offices), Halls Road (that has the Institute of Child Health and Hospital for Children) get flooded after a mild shower illustrates that the RWH structures in these buildings are just a namesake affair, as water from the setback area reaches the road.

The blame should also be on the Chennai Corporation that is responsible for constructing substandard storm water drains. “Storm water drain projects are a money spending affair. They are clogged and constructed unscientifically and don’t serve the purpose of saving rain water,” said J Saravanan, a water resource expert.

A Corporation that is dedicated to harvest rainwater in buildings has no such plan for public places. “Roads, parks, playgrounds have a land use of about 10 to 15 per cent in Chennai.Large chunks of government spaces should be harvested to conserve water,” said J Saravanan.

Stating that there should be at least one recharge well in one ground for Rain Water Harvesting, J Saravanan questions, “Is any government office following it? If yes, they should reveal the data to the public.”

 

Alyssa is a Chennai based journalist